In housing construction, a newly installed or repaired vent and wastewater system must remain isolated from the sewage service line until the plumbing construction is inspected and certified. It is common practice within the construction industry to place an outlet end of a newly installed wastewater line of the building near an inlet to a sewage service line. At this point in construction, these two lines are not connected. Where these two lines would otherwise meet, each line is capped-off until testing and inspection is complete. Usual construction techniques often require that the connection site be buried before the tests are performed. After the testing and inspection is complete, the connection site is re-excavated and a proper connection of the two lines is made.
Various patents have been issued with respect to test or isolation valve assemblies.
Sullivan (U.S. Pat. No. 4,429,568) discloses a closure plug for pressure testing a liquid drain and vent plumbing type system. Sullivan uses a cleanout Y for access to open the plug plate assembly.
Cohen (U.S. Pat. No. 1,720,819) discloses a test T having a tapered gate which closes off a house drain pipe from a drainage system. After the test has been completed, the gate is removed from the test T and the resulting opening in the tee is closed by a cover plate.
Tagliarnio (U.S. Pat. No. 4,542,642) discloses a test tee having a plug which is a removable blocking disk. The blocking disk engages a ledge in the test tee and seals the drainage system. The disk is accessible and removable through an access means.
Roberson (U.S. Pat. No. 4,658,861) discloses a pneumatic plug inserted through a cleanout T to block off a house service line to a main sewer line.
Kennedy (U.S. Pat. No. 1,948,220) discloses a test plumbing system using a flap valve which is pivoted at an upper side of a valve seat. The flap valve is held in position by a valve adjusting rod.
Barber (U.S. Pat. No. 4,602,504 and U.S. Pat. No. 4,706,482) discloses a device and method for pressure testing pipe and fitting systems in which a frangible seal disk having a removable central portion is permanently attached to the inside of a fitting placed inside a pipe section to be tested thereby blocking fluid flow. After testing, the frangible portion of the sealing disk is removed to permit fluid flow through the seal.
Mayfield, et al. (U.S. Pat. No. 4,142,371) describes a closure apparatus for tubular members in which a seal has a flexible inlay spirally imbedded therein which is torn away to destroy the seal of the structure to the conduit.
The invention described below improves upon the operation of the many prior devices described above in that it permits pressure testing of the wastewater conduits in which it is installed yet is readily removed completely from the conduit after the test is completed without the need for time consuming disassembly of the vent and wastewater conduit assemblies and without the need to reconnect the wastewater conduit to the sewer service line to commence service.